The first measurement is distance from your PAP to the pin. The second measurement is usually the distance from your PAP to your CG, although with asymetrical balls, some people use the second measurement for distance from your PAP to the MB. When they are equal, e.g. 3 3/8" x 3 3/8" it is usually referred to as stacked.
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dR3w
"I did nothing. I did absolutely nothing, and it was everything I thought it could be. "